MR Spectroscopy as a Diagnostic and Outcome Measure in Pain and SCI

Inclusion Criteria: 1. SCI and neuropathic pain: * fluent in English * incomplete or complete traumatic SCI * the injury must have occurred at least 2 years prior to entering the study * the injury level must be above L1 and the subjects must have evidence of preserved distal cord functions (lower extremity reflexes and bulbocavernosus or anal wink reflexes) * must have experienced chronic neuropathic pain at or below the level of injury for a minimum of six months * must have moderately severe or greater neuropathic pain * must be able to attend three sessions ranging from 2 to 6 hours over a period of 4 to 5 weeks 2. SCI and no neuropathic pain: \- same as a., but participants in this group must NOT have unremitting moderate-severe pain and there will only be two sessions ranging from 2 to 6 hours over a period of 1 to 2 weeks 3. Able-bodied control subjects: * fluent in English * no history of chronic pain conditions * no substantial brain or body injury * must be able to attend two sessions ranging from 2 to 6 hours over a period of 1 to 2 weeks Exclusion Criteria: * current pregnancy or women who are contemplating pregnancy * recent (one-year) history of alcohol or drug abuse * known intra-cerebral pathology or epilepsy * MRI findings indicative of intra-cerebral pathology * significant post-traumatic encephalopathy from head trauma sustained at SCI or cognitive impairment indicative of traumatic brain injury * current diagnosis of DSM-IV Axis I disorder * inability to meet the MRI screening requirements (including, but not limited to, the presence of a pacemaker or other electronic devices, prosthesis, artificial limb or joint, shunt, some metal rods, some tattoos, or moderate to severe claustrophobia or anxiety)